Preparation Of High-quality Plasmonic Crystals And Research On Their Sensing Characteristics

Surface plasmon polaritons refer to the sparse electron waves propagating along the metal surface generated by the interaction of freely vibrating electrons and photons existing on the metal surface.Surface plasmons have been widely explored in sensing,waveguides and particle trapping since they have the ability to break the diffraction limits.With the continuous development of nanoparticle synthesis and nanomanufacturing technology and in-depth study of theory,plasmon polariton sensing have attracted much attention in the fields of environment and biosensing,and have become one of the most popular applications.For a plasmon sensor,the excellent quality factor can ensure its better sensing performance,and the properties of the plasmon can be affected by changing the structure parameters.Based on two-dimensional periodic nanostructures,this thesis studies its sensing performance.The main work of the paper is as follows:First,a method of monolayer composite microsphere arrays prepared by sol-gel cooperative self-assembly method was proposed.The proposed monolayer composite microsphere arrays provides a flexible platform for producing universal plasmon structures by adjusting the gel penetration height or the thickness of the sputtered metal film.Experimental studies have investigated manufacturing factors that affect the quality of monolayer films,such as ambient humidity,evaporation temperature,and the concentration of tetraethyl orthosilicate solution.Using the correlation function to evaluate the order of the experimental results,the high order of the composite microsphere array is revealed.By adjusting the parameters of the structure and the thickness of the metal film,the figure of merit of the surface plasmon polaritons excited on the array is adjusted.Next,a miniature micro-pressure sensor based on the plasmonic cavity is proposed.Above the silicon sensitive film,two gold displacement columns symmetrical about the center of the sensitive film are sputtered,so that an air cavity with a certain length is formed between the two cubes.By applying pressure to the silicon film to deform it,the displacement column is driven to generate a displacement tilt and the cavity length is changed.Moreover,the parameters of the silicon film are determined according to the mechanical properties.On this basis,the optical properties of this structure are discussed,and the interaction between the SPP Bloch wave mode and the FP cavity mode within this microcavity is studied.This structure is simulated using a finite-difference time-domain algorithm to determine the parameters of the cube.In addition,the reflectivity spectra under different pressures were simulated,discuss the relationship between pressure and SPP characteristics,and wavelength drift,so as to obtain the sensitivity corresponding to this structure.